Pros and Cons of the Framingham Risk Calculator

The Framingham risk calculator is a tool used to predict your risk of heart disease. It is based on information gained from the Framingham Heart Study (FHS), a long-term, ongoing health study of people in Framingham, Massachusetts, that began in 1948. The study helped establish that heart disease is linked to smoking, high cholesterol, and high blood pressure.

Using information from the FHS, the risk calculator provides a cardiac risk score, which helps predict a person's risk of heart disease. This article discusses the pros and cons of the Framingham risk calculator, as well as other cardiac risk calculators.

What the Framingham Risk Calculator Measures

The first Framingham calculator, published in 1998, measures your risk of developing coronary artery disease (CAD). CAD, sometimes called coronary heart disease (CHD), happens when fatty deposits (called plaques) form within the arteries that supply blood to your heart.

The calculator was based on data from 5,345 people the FHS followed over 12 years. Researchers found that CAD disease was largely associated with certain levels of blood pressure, total cholesterol, and LDL (low-density lipoprotein) cholesterol.

Risk factors were determined by comparing characteristics of the people in the group who did or did not develop angina (intense chest pain), heart attack, or death from heart disease. An algorithm for predicting the 10-year risk of these outcomes was created.

Who Should Use It?

The original Framingham calculator was designed as a tool to predict CAD risk in people ages 30–74 who had no history, diagnosis, or symptoms of CAD. It includes separate score sheets for men and women.

Your healthcare provider will use the results of risk calculators to recommend preventive strategies through lifestyle changes, and potentially cholesterol-lowering medications.

How the Framingham Risk Score Is Calculated

The original Framingham calculator includes tallying risk factors on a gender-specific score sheet to determine your 10-year risk for CAD.

Points are assigned based on the presence or level of the following risk factors:

• Age
• LDL cholesterol or total cholesterol
• HDL (high-density lipoprotein) cholesterol
• Blood pressure
• Diabetes
• Smoking status

Adding the points for each risk factor provides a score. This score indicates your 10-year risk for CAD.

The original Framingham calculator provided an important framework for CAD risk assessment and has been modified over time as our understanding of heart disease improves.

In 2008, another update to the Framingham Risk Score was published that broadened the definition of CAD to include other atherosclerotic disease complications of stroke, claudication (pain due to peripheral artery disease), and heart failure.

In addition to the 10-year risk of heart disease, the updated Framingham Risk Score provides an "estimated vascular age." Vascular age essentially determines the age of your arteries based on criteria like your age, overall health, and present risk factors. The notion of vascular age theorizes that a person is as old as their blood vessels.

For example, a hypothetical 40-year-old man who smokes but has other risk markers in the normal range has a vascular age of 46. This means he has the same level of risk as a 46-year-old man who does not smoke and has normal markers. Smoking has added six years to this man's vascular age.

Where to Take It

The original Framingham calculator can be found online here. It includes separate charts for men and women and provides a 10-year risk of CAD, including angina, heart attack, and death from CAD.

The updated ATP-III Risk calculator can be found online here. It's referred to as "hard coronary heart disease," because it uses only hard endpoints of heart attack or death from CAD, and does not include angina.

Both tests have separate sections for men and women. Tables are used to determine points for the various risk factors. Note that in the original Framingham risk calculator, either total cholesterol or LDL cholesterol can be used. This will affect how you read the points in some of the other tables.

The updated Framingham risk calculator can be found online here. This is a straightforward test that requires providing cholesterol and blood pressure numbers and noting other risk factors. It gives a 10-year risk of heart disease, including CAD, stroke, heart failure, and peripheral artery disease, as well as estimated vascular age.

Is It Accurate?

The Framingham risk calculator is an important early risk assessment tool for heart disease that's provided a framework for future risk calculators. It has been validated for various populations in multiple studies. Yet, it's been found to either overestimate or underestimate risk in certain populations.

The original Framingham risk calculator was based on a homogenous group of mostly White people near Boston. Since then, additional risk calculators have been developed and refined to provide more accurate predictions that are more representative of all populations in the United States.

Pros

• Based on solid epidemiologic data from the well-designed Framingham Heart Study
• Among the first risk calculators to include multiple ranges for blood pressure, rather than using the presence or absence of hypertension (high blood pressure)

Cons

• Includes a homogenous group of mostly White people
• Underestimates risk in women
• Overestimates risk in populations with a low incidence of CAD
• Provides risk only over 10 years

Other Cardiac Risk Calculators

Since the original Framingham calculator, several other calculators have been developed that take into account data from studies with more diverse groups of people.

Below are some calculators of importance for their inclusion of other populations and for their use in clinical practice.

The Reynolds Risk Score

The Reynolds risk calculator was first developed to provide a more accurate risk assessment in women, since it was noted that other risk assessments significantly underestimate their risk. The original Reynolds Risk Score was meant to be taken by women ages 45–80 without diabetes. A version for men was later created.

Compared to the Framingham Risk Score, the Reynolds Risk Score includes other risk markers for heart disease such as C-reactive protein (CRP), which is an inflammatory marker in the blood, and a family history of heart disease.

Atherosclerotic Cardiovascular Disease Risk Calculator

In 2013, the American College of Cardiology (ACC) and American Heart Association (AHA) developed the Atherosclerotic Cardiovascular Disease (ASCVD) Risk Calculator, which is based on the pooled cohort equations (PCE). The PCEs are several studies that include multiple populations and demographics in the United States.

The calculator was updated in 2018 to provide a further breakdown of risk categories:

• Less than 5% (low risk)
• 5% to less than 7.5% (borderline risk)
• 7.5% to less than 20% (intermediate risk)
• Greater than or equal to 20% (high risk)

Current guidelines recommend that healthcare professionals use this calculator to assess the 10-year risk of heart attack and stroke in people also at risk of atherosclerosis. The ASCVD Risk Estimator Plus can be found online here.

Risk factors included in the calculator are the same as those in the Framingham calculator, with the addition of race, history of diabetes, and use of antihypertensive medication.

While the Framingham calculator was comparably limited because data came from a homogenous White population, the ASCVD risk calculator includes ethnicity as part of the calculator. It also provides information that risk may be underestimated for American Indians, people of South Asian ancestry, and Puerto Rican people, and overestimated for Mexican Americans and those of East Asian ancestry.

Interpreting Your Score and Making a Plan

After calculating your risk score, discuss the results with your healthcare provider. Risk scores are a good tool for general recommendations in a population, but a healthcare professional can provide a recommendation for your specific situation.

Certain groups of people may have an overestimated or underestimated risk. Other risk factors that aren't included in the calculator can contribute to an even higher risk.

Even though they're not included in the calculator, kidney disease, inflammatory disease, and a family history of heart attack at a young age further increase the risk of heart disease.

Women who have had early menopause or a history of preeclampsia also have a higher risk.

Your healthcare provider may recommend specific lifestyle changes, like increasing physical activity and making dietary changes, before considering medication. Some people who are on the borderline of starting cholesterol medication may benefit from a special CT (computed tomography) scan that measures coronary calcium.

Summary

The Framingham risk calculator, based on health data from the Framingham Heart Study, is a tool used to predict a person's risk of heart disease. Despite its benefits for predicting disease, it has been known to either overestimate or underestimate risk in certain people, and it did not include more diverse populations of people. Newer risk calculators have been designed differently, some of which account for race, gender, or existing medical diagnoses.

A Word From Verywell

Cardiac risk assessment calculators are important tools for predicting your risk of heart disease. Thanks to the landmark Framingham study, our understanding of heart disease risk continues to improve. Current guidelines recommend the ASCVD calculator. Your results should always be discussed with a healthcare provider who can make personalized recommendations based on your specific situation.